1. Without allowing to limit your search by category, your visitors will always have more results.
2. If you want to allow to allow selecting one or more categories only (instead of all categories), then you cannot add the search to the search bar itself, but will need to add it to the custom search box. Currently your category search is added to the search bar, so you will never see it in the customised search box. I have now changed that for you.
3. When we click on, Sawmills and Logging or Sawmill alone – it returns no results.
Your custom search settings were set to “AND” is so the the only results returned must be in ALL categories selected. If “OR” is selected then the search will return listings that are in one or more of the categories.
See image.
4. Can you explain what you mean with “We have also discovered your search radius doesn’t work very well, and several other issues.” so we can try to assist.
5. I also alerted other support to review your questions.
Thanks